题目描述

差分矩阵

模板分六步

1、先写出 insert() 函数 ;
2、读取数据 a[ ] ;
3、计算差分 d[ ] ;
4、调 insert() 函数 +c ;
5、求前缀和 ;
6、遍历输出 ;

#include <iostream>
using namespace std;
#define int long long
const int N = 1010;
int a[N][N], d[N][N];

void insert(int x1, int y1, int x2, int y2, int c)
{
    d[x1][y1] += c;
    d[x1][y2+1] -= c;
    d[x2+1][y1] -= c;
    d[x2+1][y2+1] += c;
}
signed main()
{
    int n, m, q;
    cin >> n >> m >> q;

    // 先读取
    for (int i = 1; i <= n; i ++ )
        for (int j = 1; j <= m; j ++ )
            scanf("%lld", &a[i][j]);
    // 再算差分
    for (int i = 1; i <= n; i ++ )
        for (int j = 1; j <= m; j ++ )
            insert(i, j, i, j, a[i][j]);

    // 计算        
    while(q--)
    {
        int x1, y1, x2, y2, c;
        scanf("%lld%lld%lld%lld%lld",&x1,&y1,&x2,&y2,&c);
        insert(x1,y1,x2,y2,c);
    }

    // 求前缀和
    for (int i = 1; i <= n; i ++ )
        for (int j = 1; j <= m; j ++ )
            d[i][j] += d[i - 1][j] + d[i][j - 1] - d[i - 1][j - 1];

    // 遍历输出
    for (int i = 1; i <= n; i ++ )
    {
        for (int j = 1; j <= m; j ++ ) printf("%lld ", d[i][j]);
        printf("\n");
    }
    return 0;
}